The present invention relates generally to a method of mounting hold down hardware that is adapted to transfer tension loads between floors and concrete foundations. Such hold down hardware devices have become common to tie together wood-framed wall sections to concrete or masonry structures. The present invention is more particularly a method of drilling true elongated holes in wood support members for mounting hold down hardware used in the construction of various types of buildings. Such hold down devices are generally employed when a building is being built, since major construction projects incorporate wood framed sheer walls or the like that must satisfy stringent load bearing specifications.
The method of the present invention is more particularly useful in areas where earthquakes are prevalent. Retrofitting of old buildings must comply with seismic requirements that are now required in several states. This is particularly true with respect to earthquake damaged buildings that must comply with new retrofit code requirements d&fined by federal, state or county agencies.
Retrofitting is a very tedious and time consuming job and thus is an expensive operation. However, the present invention indicates that a substantial amount of savings in the cost of retrofitting can be realized because of the innovative method of mounting the hold down hardware members.
The major time consuming operation in the art of retrofitting structures occurs when hold down hardware is required to be mounted to a vertical, load bearing, structural member or beam that must be inserted in or together with a wall wood frame structure.
Commonly, vertical bearing members, generally referred to as studs, are used in sizes such as 2.times.4's, 2.times.6's, 2.times.8's and some even wider such as 4.times.6's, 4.times.8's, etc. However, to better understand the problem when retrofitting, load bearing beams are very often defined as elongated boards that often exceed the usual dimensions as noted above. Therefore, it is common to find that load bearing beams can be formed in various sizes of approximately 3.about. inches or more in width and 30 inches or more in depth, requiring the drilling of a plurality of very straight aligned bores or holes in the beams to receive respective elongated bolts which are readily inserted so as to extend from one side to the other of the beam without binding.
Until the present method, as described herein, large board members were bored by first drilling from one side of the board and then drilling from the opposite side in hopes that the two oppositely disposed bores would be aligned with one another so as to define a fast true hole or bore to receive the corresponding elongated bolt. To allow each bolt to readily passed through its respective bores, it must be positioned to correspond to the aligned, equally spaced holes located in a given hold down member. Thus, the bolt receiving bores are required to be in perfect parallel alignment with each other.